Mold making machine with rollover device



Aug. 24, 1954 .1. H. WILLIAMS MOLD MAKING MACHINE W-ITH ROLLOVER DEVICE9 Shee ts-Sheet 1 Filed Feb. 4, 1953 1, mmvroa JAMES HOWARD WILLIAMSATTORNEY 1954 J. H. WILLIAMS 2,686,945

MOLD MAKING umcnms wrm ROLLOVER DEVICE Filed Feb. 4, 1953 I9Sheets-Sheet 2 INVENTOR. JAMES HOWARD WILLIAMS ATTORNEY Aug. 24, 1954 J.H. WILLIAMS MOLD MAKING MACHINE WITH ROLL-OVER DEVICE 9 Sheets-Sheet 3Filed Feb. 4, 1953 INVENTOR.

JAMES HOWARD WILLIAMS ATTORNEY 9 Sheets-Sheet 4 ATTQRNEY Aug. 24, 1954J. H. WILLIAMS MOLD MAKING MACHINE WITH ROLLOVER DEVICE Filed Feb. 4,1955 Aug. 24, 1954 J. H. WILLIAMS 2,686,945 MOLD MAKING manna: wrmROLLOVER DEVICE Filed Feb. 4, 1953 9 Sheets-Sheet 5 v INVENTOR. JAMESHOWARD WILLIAMS ATTORN EY ug 1954 J. H. WILLIAMS 2,636,945

MOLD MAKING MACHINE WITH ROLLOVER DEVICE Filed Feb. 4, 1953 '9Sheets-Sheet 6 JAMES HOWARD WILLIAMS BY v ATTOR N EY Aug. 24, 1954 J. H.WILLIAMS 2,636,945 MQLD MAKING MACHINE WITH ROLLOVER DEVICE Filed Feb.4, 1953 9 Sheets-Sheet 9 FIG.I7

INVENTOR. JAMEi HOWARD WILLIAMS ATTOR N EY Patented Aug. 24, 1954 UNITEDSTATES PATENT OFFICE MOLD MAKING MACHINE WITH ROLLOVER DEVICE JamesHoward Williams, Lincoln, R. I., assignor to Grinnell Corporation,Providence, R. I.,. a corporation of Delaware Application February 4,1953, Serial No. 335,087

mechanism grips the squeeze-boards as the mold is turned over, makingunnecessary special clamps or other means of securing together theassembly of flasks and match plate.

Yet another object of my invention is to provide in my novel mold makingmachine an elec trical control system so arranged that maximum number ofmachine operations follow each other automatically, thus reducing thenumber of levers or switches and requiring less attention on the The oldmatch plate method of producing sand part of the operator to see thatthe proper semolds, and, as far as I am aware, the match plate quence isfollowed.

method still most widely practiced in industry, And finally it is anobject to provide a machine has a serious disadvantage in that itrequires conpart of which may be easily removed for maintesiderablehandling of heavy sand-filled flasks on nance and repair. the part ofthe workman. Machines were early The best mode in which I havecontemplated devised for properly squeezing the sand in the applying theprinciples of my improvements is flasks, but when the most eflicient useis made shown in the accompanying drawings, but these of these machinesthe assembled flasks and the are to be deemed merely illustrative for itis in match plate resting thereon must be turned over tended that thepatent shall cover by suitable after each squeeze at which time bothflasks are expression in the appended claims whatever feafilled withsand and are very heavy. tures of patentable novelty reside in theinven- From time to time other mold making mation disclosed. chines havebeen proposed which tend to mini- In the drawings: mize the amountofhandling required of the Figure 1 is a front elevation View of my imworkman by automatically turning over the proved mold making machinewith portions shown assembly of flasks and match plate after perinsection; forming the squeeze. Some of these machines Figure 2 is a sideelevation view of the machine have been used commercially for 'a numberof taken as online 22 of Figure 1; years with moderate success, but allthose that Figure 3 is a plan view of the machine taken as have come tomy attention are so constructed on line 3-3 of Figure 1; that they mustbe provided with specially de- Figure 4 is a front elevation view of theupper signed cope flasks, drag flasks and match plates end of one of theclamping legs of the roll-over "for use therewith. For the most parthowever, mechanism and the clamping head associated the match plates andflasks now employed in the therewith, portions of these elements beingshown old match plate method represent a considerable 5 in crosssection; investment, and there is an understandable re- Figure 5 is adetail of the roll-over mechanism luctance in industry to replace theseitems as well not shown in Fig. 4; as the machines with which they haveso long Figure 6 is a perspective view showing how the been used.clamping jaws grip the mold during the roll-over It is an object of thepresent invention to prooperation. Portions of the flasks are cut awayto vide a mold making machine, adapted to the show the assembly offlasks and match plate; match plate method of molding,'in the operationFigure 7 i a diagram showing a cope flask, of which no special flasks ormatch plates are drag flask and match plate assembled on the table.necessary, equipment of this sort which has long The drag flask isfilled with sand and lowermost, been used in the predominantly manualmethod 5 having been prepared and turned over on the being accommodatedby my novel machine. table by the operator;

Another object of my invention is to provide Figure 8 is a diagramshowing the cope flask a mold making machine. which has the usual filledwith sand; squeeze mechanism and in addition has a mecha- Figure 9 is adiagram showing the squeeze top nism for turning over the mold, asrequired, durswung forward and the table raised to squeeze the ing itspreparation, thus reducing the amount of sand in the cope flask; liftingand handling required of the operator. Figure 10 is a diagram showingthe table low- Still another object is to provide a machine of ered andthe squeeze top swung back; the above described type in which theroll-over Figure 11 is a diagram showing the table raised, the clampinglegs swung in toward the 3 table and the jaws closed on the ends of thesqueeze-boards;

Figure 12 is a diagram showing the table lowered and the clamping headsA turning over the flasks;

Figure 13 is a diagram showing the flasks turned completely over so thatthe drag flask is on top, the table raised and the jaws opened;

Figure 14 is a diagram showing the clamping legs swung back, the tablelowered and the finished drag removed and placed on a nearby bench;

Figure 15 is a diagram showing a new drag flask placed in position onthe match plate,

filled with sand and ready for the same squeeze and roll over which willput the finished cope uppermost;

Figure 16 is an elementary wiring diagram of an electrical controlsystem which may be employed with my improved machine; and

Figure 1'7 is an elementary piping diagram of a fluid control systemwhich may be employed with my improved machine.

Referring now more particularly to the drawings, the general assembly ofmy improved machine is best shown in Figs. 1, 2 and 3. In its preferredembodiment this .machine comprises a portable molding machine of theconventional type having a fluid pressure operated squeeze mechanism anda manually positionable head in the usual form, but which is mounted ona fixed base, the wheels having been removed for that purpose, and withwhich there is associated mechanism for turning over the molds beingprepared. More specifically the SP No. 1103 Portable Jolt SqueezeMolding Machine made by SPO, Incorporated, of Cleveland, Ohio, is welladapted for use in the present improvedrnachine, though it will beunderstood that other squeeze mechanisms which operate in the samegeneral way may be used.

As shown in the drawings the squeeze mechanism includes a squeezecylinder Ni disposed with its axis vertical and provided at .itsunderside with short depending legs Ma which serve as bearings for ahorizontal axle [2, the ends 1211 of which project from either side ofthe cylinder ill and are customarily fitted with wheels. In the presentinvention, however, these wheels have been removed and the ends 120, ofthe axle i2 are supported in semi-circular open journals 14a formed insupporting plates M (see Fig. 2). These supporting plates are arrangedgenerally perpendicular to the axis of the axle t2 and have end flangesMb bolted or otherwise secured to upstanding brackets l6 which are inturn suitably fastened to a base plate 18 resting on the floor. A table28 is located across the upper end of the squeeze cylinder and connectedto a piston 22 therein by a piston rod 24. This table is moved upward byintroducing fluid pressure into the cylinder below the piston. Theweight of the table is sufficient to bring it down again when the fluidpressure is exhausted from below the piston.

Integrally formed with the squeeze cylinder H3 at the back thereof andextending rearwardly therefrom is a frame member [0b, bifurcated at itslower end to accommodate a third wheel which has been removed in thepresent invention and a bearing bracket 26 2substituted therefor. Thisbearing bracket is secured in a convenient manner to a raised portion18av of the base plate i8 and carries a short axle 28 on the ends ofwhich the bifurcated portions of the frame member 19b are mounted.Elsewhere on this frame member lfib there are pivotally secured thelower ends of two upstanding arms 30 and 32 which comprise partsof asqueeze-head linkage, the upper ends of these arms being pivotallysecured to a squeeze-head cross bar es, substantially as shown. Asqueeze-head 36 is fixed to the cross bar 3 3 at the end thereof nearestthe squeezecylinder ii], the linkage as a whole being arranged so thatthe squeezemead 3% may be swung forwardto a position directly above thetable 28 as shown in Fig. 2 or swung back a predetermined distance tothe position illustrated in Figs. 1 and 3. A series of pivot holes 30aat the upper end of arm 3i) and a corresponding series of holes 32a atthe upper end of arm 32 provide for adjustment of the distance betweenthe movable table 29 and the squeeze-head 35 making possible the use ofa wide range of flask sizes, as will be more fully understood. Thus, inthe operation of the machine sand in the flasks placed on tables 28 isproperly squeezed by raising the table when the squeeze-head 36 is inits forward, position above the table. Because of the adjustability ofthe squeeze-head, made possible by the series of pivot holes 36a and32a, flasks of substantially different depths may be employed.

Mcvement of the squeeze-head 36 to and from its forward position abovetable 26 is achieved by a fluid pressure actuated piston-cylinder unit Athe cylinder 3% of which has one of its ends 38a pivotally mounted onthe raised portion 28a of the base plate It by means of a bracket 35secured to this portion behind the bearing bracket 2%. A piston rod 42fixed to a piston within the cylinder 38 and projecting from the otherend thereof has its end i2 1. pivotally secured to one of the upstandingarms 32 of the squeeze-head linkage by another bracket M. This bracket44 also serves to clamp against the arm 32 one end of a leaf spring litthe other end of which bears against a self-aligning plate 48- mountedon the fixed frame member Nib as shown. This leaf spring tends to urgethe squeeze-head 36 into this forward position above the table 20, thusaiding the piston cylinder unit A into overcoming gravity since thelinkage is so arranged that the squeeze-head swings upward as well asforward from its rearmost position. The extent of swing of thesqueeze-head $6 is limited by the stroke of the piston in the cylinder33.

On either side of the squeeze cylinder it there is located a clampingleg 5i! pivotally mounted on a horizontal axle 52 which is supported bybearings 5 lsecured to the base plate l8 and which is so disposed thatthe clamping leg 56 pivoted thereon swings toward and away from thetable 20. Swinging movement of these clamping legs is achieved by twoadditional fluid pressure actuated piston-cylinder units B, thecylinders 56 of which are pivotally mounted on horizontal trunnions 53between the pairs of upstanding brackets [6 located on either side ofthe squeeze cylinder Hi. Piston rods '65) fixed to pistons within thesecylinders 56 have their ends 60a pivotally secured to the clamping legssubstantially as shown. The simultaneous introduction of fluid pressureinto the two cylinders 56 on corresponding sides of the pistons thereincauses the clamping legs 50 to swing in or out as the case may be.

These clamping legs 59 comprise the supports for what may be termedroll-over clamping heads C located in their upper ends. Each of theseroll-over clamping heads has associated therewith, in a manner whichwill be more particularly described, a pair of rotatable jaws adapted togrip the flasks, when the table 20 has been raised the proper distance,and turn over the flasks, when the table is again lowered. During thispart of the machines operation, that is, when the flasks are beingrolled over, the clamping legs are moved to a substantially verticalposition as shown by the solid lines in Fig. 1. For the remainder of themachine cycle the clamping legs are swung back to the position shown bythe dotted lines in Fig. 1 and out of the way of the operator working onthe flasks on the table 20. The extent of outward swing of each clampingleg 59 is limited by the stroke of the piston within cylinder 56, andthe extent of inward swing of each clamping leg is limited by anadjustable bolt 62 which is threaded in a cross bar M secured across theupstanding brackets I6 and against the end of which the clamping legcomes to rest.

Formed in the upper end of each of the clamping legs 50 is a largecircular hole 5011 (see Fig. 4)

particularly each of these roll-over clamp-ing heads comprises acylindrical body 68 which fits nicely within the ball bearing units 66.In its preferred form this cylindrical body is externally threaded at68a, the portion adjacent the center of the clamping leg hole 50a, toreceive an internally threaded annular ring 10. When installed in theclamping leg hole 50a with suitable filler washers 12, 12a and 72b theroll-over clamping head 0 is prevented from moving axially bythisannular ring 10 which is confined oneither side by the ball bearingunits 66, and these two ball bearing units are in turn prevented frommoving laterally by two annular dust covers 14 bolted to the clampingleg at either end of the hole Ella. The cylindrical body 68 of theroll-over clamping head C has a central passage 68b of large.

diameter partway therethrough in which a piston 76 is nicely fitted. Asmaller central passage 680 through the end wall of the cylindrical bodyaccommodates a piston rod 18 which is fixed to the piston l5 and whichactuates the rotatable jaws.

The piston rod passage 680 is provided with the usual packing gland 80to prevent leakage of fluid pressure around the piston rod. The otherend of the cylindrical body 68 opposite the piston rod passage 680 issealed by a plug 82 bolted to the periphery of the cylindrical body witha suitable sealing gasket .84 interposed in the usual manner thuscausing the central passage 68b to become a pressure tight chamber.Fluid pressure is admitted to this chamber on one side of the piston 16through a duct 82a centrally located in the plug 82, and fluid pressureis admitted on the other side of the piston through another duct 82?) inthe plug which joins a duct 68d in the side Wall of the cylindrical body68.

During one complete machine cycle the rollover clamping head C rotates180 in one direction and then in the next machine cycle rotates backagain 180 in the opposite direction, and so on. Consequently, it isnecessary to provide means for admitting fluid pressure to the ducts 82aand 82b in the rotating plug 82 from fixed supply pipes. This could bedone by using rubber hose connections or other flexible leads joined tothese ducts in plug 82 and free to rotate therewith, but the structureshown is preferred because the leads from the fixed supply pipes do notrotate and as a result there is no danger of their becoming entangled.To accomplish this preferred result the plug 82 has extending from italong the axis of the roll-over clamping head C a cylindrical shaftportion 820 on the outer end of which is rotatably mounted a spool 86.This spool has ball bearing units 88 located in recesses 86a at bothends thereof to permit free turning of the plug shaft 820 with respectthereto. An annular dust cover 90 bolted to the end of the spool nearestthe clamping leg 50 confines the ball bearing unit 88 located therein inits recess 86a. and at the other end of the spool the other ball bearingunit 83 is confined in its recess by a nut 92 which is threaded onto theend of the plug shaft 820 and which also serves to prevent the spool 86from moving axially thereon. l A flanged cup 94 (see Fig. 5) is boltedto the end of the spool 86 across the end of the plug shaft thus forminga pressuretight chamber 96 into which fluid pressure is introducedthrough a connection 94a in the flanged cup. From this chamber 96 fluidpressure enters the duct 82a extending along the plug shaft 820 and isled to chamber 682) on one side of the piston It to move the piston inone direction.

To move the piston in the other direction fluid pressure must enter duct321). This duct also extends along the plug shaft 320 but near the outerend thereof turns and opens into an annular groove 3202 which isenclosed by the body of the spool 86 and made tight by sealing rings 98forming a pressure chamber I99. Fluid pressure is brought to thispressure chamber through a connection 862) in the side wall of the spool86 opposite the groove 8203. No matter how the plug shaft 820 turnswithin the spool 86 fluid it pressure admitted to pressure chamber Qtcan enter duct 82a, and likewise fluid pressure admitted to chamber H30can always enter duct 82?).

In one of the two roll-over clamping heads a third duct 82a is locatedin the plug 32 and joins a second duct 82c in the sidewall of thecylindrical body 68. Unlike duct G861, however, this duct Ste does notenter the chamber 6821; but emerges from the cylindrical body near therotatable jaws and is provided at this point with a fluid pressureconnection Hi2 for a short length of flexible hose Hi l. The other endof this exible hose has connected to it an air vibrator flit (see Fig.6) whose function will be explained presently. The duct 826 extendsalong the plug shaft 820 and enters a groove S2 in the side thereofadjacent the groove 82d. This groove 82 is also enclosed by the body ofthe spool 8t and made tight by sealing rings Hi8 forming a pressurechamber llfi. Fluid pressure is brought to this pressure chamber througha connection the in the side wall of the spool 86.

The air vibrator N35 is bolted to the match plate H2 (see Fig. 5)located between flasks H t and I It and is turned on at the end of amachine cycle when the operator lifts a finished flask from the matchplate. The vibration it provides prevents the sand in the flask fromsticking to the contours of the match plate. However, during eachmachine cycle the match plate H2 is turned over and with it the vibratorN56. The flexible hose I04 bringing fluid pressure to this vibratorwould become entangled with the jaws if it were connected directly to afixed fluid pressure supply pipe, but by the improved arrangement theflexible hose HM rotates with the match plate and cannot becomeentangled or twisted.

Referring again to Fig. 4, the force exerted .by fluid pressure inchamber 6% moves a thrust lever H8 secured across the end of piston rodit and arranged substantially parallel to the ciamping leg .528. Thisthrust lever has pivotally secured to its ends identical short linksI20, the

other ends of which are pivotally secured to clamping jaw holders 1.22.These clamping jaw holders are themselves pivoted to projections $3formed on the cylindrical body 58, substantially as shown, and areprovided with adjustment teeth 122a to mesh with corresponding teeth 2301 on the rotatable jaws 12d bolted to the clamping jaw holders bybolts i26. of teeth on the jaws and jaw holders the distance between theclamping jaws may be adjusted to accommodate different flask sizes byloosening the bolts Hit, moving the rotatable jaws to a new position onthe clamping jaw holders and then tightening these bolts until the teethl22a and t l-a are again meshed. Ihe jaw linkage as a whole issoarranged that movement of thrust lever HS in one direction spreads therotatable jaws I25 apart, and movement in the opposite direction closesthe rotatable jaws.

Rotation of each roll-over clamping head C in its hole 553a .is achievedby a fluid pressure actuated piston-cylinder unit D (see Figs. 1 and 2),the cylinder l28 of which i pivotally secured at one end ia to aprojection 55?) extending outward from the side of the clamping leg Apiston rod its is fixed to a piston within this cylinder 128 and has itsend pivotally secured to a segment gear I32 which is in turn pivotallymounted in bearings i3 2 bolted to the clamping leg so that the segmentgear can engage a pinion gear 36 keyed to the plug 532 behind spool 8%.Movement of the piston rod I38 turns the segment gear n32 which rotatesthe pinion gear Kit and thereby rotates the roll-over clamping head C inthe clamping leg hole 58a. Consequently, the rotatable jaws I24 rotateand turn over the flasks gripped between them.

During the roll-over operation of the machine it is necessary to achievea rotation of the rollover clamping head C of exactly 180 and this isaccomplished. by means of adjustable stop bolts ESE mounted inprojections 560 formed on each clamping leg so. These bolts are sodisposed with respect to the segment gear l32 that a hub i32a thereonstrikes against the end of one of these bolts at either end of itsswing. Proper adjustment of the bolts I38 in their projections 580 willlimit the rotation of the roll-over clamping head 0 to exactly 180 andproperly fix the position of the rotatable jaws at the end of theirtravel.

Referring now more particularly to Figs. '7 to 15, the sequence of stepinvolved in the production of a sand mold using my improved machine isas follows: First the operator puts an empty cope flask H6 upside downon table 20. Next he places the match plate H2 across the cope flask andputs an empty drag flask ll l on this match plate. Aligning pins lltafixed to the ends of the cope flask fit into suitable holes 2a and H40;in the ends of match plate and drag flask, respectively, and serve tokeep these parts .of the assembly proper alignment (see Fig.

With this provision 6). The operator then 13115 the empty drag flask litwith sand Mt from an overhead hopper (not shown) and with a suitabletool (for instance. a shovel handle) tamps the sand until it is packedfirmly. Next the operator levels off the packed sand until it is flushwith the edges of the drag flask H t and places a squeeze-board M2 onthe sand. This squeeze-board fits just inside the edges of the flask.Then the operator turns the entire assembly over by hand so that thesandfilled flask I ii is resting on its squeeze-board M2 on the table atand the empty cope flask i it is uppermost. See Fig. '7.

It is necessary to hand-tamp this first drag and turn the assembly overby hand for two reasons; First of all the sand in the drag flask cannotbe squeezed by the machine because there is no sand in the cope flaskbelow, and consequently there is a danger that the match plate H2 mightbe bent by the force of a machine squeeze. Secondly, the rotatable jaws124, which grip the assembly of flasks and match plate during themachine roll over, are arranged to engage the squeeze-board I42 and acorresponding squeezeboard Ni l, as illustrated in Fig. 6, and nosqueezeboard can be put in place in the cope flask H6 because this flaskis empty.

Having turned the flasks over by hand, as indicated, the operator thenfills the empty cope flask H5 with sand from the hopper, levels off thesand and places the squeeze-board I44 thereon. See Fig. 8.

Next the operator pushes a squeeze-roll button Hit on a control panel MSof the electrical system and the following operations take place.Pushing this button initially causes fluid pressure to be admitted tocylinder 38 swinging the squeeze head 36 to its forward position abovethe assembly of flasks and match plate .on the table 26. At the end ofthe forward movement of the squeeze-head a projection 321) on theupstanding arm 32 of the squeeze-head linkage trips a head-forward limitswitch I50 suitably mounted on frame member lilb. (The various limitswitches herein referred to are shown in Figs. 1, 2 and 3.) As a resultof this switch being tripped the electrical control circuit causes fluidpressure to be admitted to the squeeze-cylinder it whereupon table Zllbegins to move upward, carrying the assembly thereon toward thesqueeze-head 33. The table continues upward until the squeeze-board M4on the sand in the cope flask engages the squeeze-head 36 and the sandis squeezed. See Fig. 9.

When the pressure in the table raising cylinder it reaches apredetermined value, calculated to give the sand the proper amount ofsqueeze, a pressure switch I52 (shown in Figs. 16 and 17) trips,simultaneously closing the supply of pres- .sure to the table raisingcylinder l0 and exhausting the pressure therefrom. Consequently theweight of the table 28 and the assembly thereon carries the table backto its down position.

Near the end of the downward movement of the table a pad Hi lsadjustably mounted on a rod 5 depending from the back edge of table 20trips a table-down limit switch I58, and as a result of this switchbeing tripped fluid pressure is admitted to cylinder 38 causing thesqueezehead 36 to swing from its forward position above table 20 to itsback position. See Fig. 10.

Near the end of the backward swing of the squeeze-head a projection 30bon'the upstanding arm 30 of the squeeze-head linkage trips .a head- 9back limit switch I58 and as a result of this switch being tripped fluidpressure is admitted to the table raising cylinder I0. Consequently thetable 20 again moves upwards This time, however, the upward movement ofthe table is not limited by the squeeze-board I44 on the sand in thecope flask engaging the squeeze-head 36 because the squeeze-head is inits back position, and the table 20 travels to the top of its stroketripping a table-up limit switch IGtlwhich is engaged by a pad I02aadjustably mounted on a second rod I62 depending from the back of table20. As a result of this latter switch being tripped fluid pressure isadmitted to cylinders 56 causing the clamping legs 50 to move inwardtoward table 20 until the open rotatable jaws I24 are in a position tograb the ends of the two squeeze-boards I42and I44 when the rotatablejaws are closed.

Near the end of the inward swing ofeach of the clamping legs 50 a bar501;. fastened to each leg trips a clamping-leg in limit switch I64, andwhen both of these clamping-leg-in limit switches are tripped fluidpressure is admittedtochambers 68b in both roll-over clamping heads Ccausing the rotatable jaws I24 to close and grab the assembly on thetable. See Fig. 11.

When the pressure in both chambers 68b reaches a predetermined valuecalculated to assure proper gripping by the rotatable jaws, twoadditional pressure switches IE6 and I68 (shown in Figs. 16 and 17)aretripped, and as a result of these pressure switches being trippedfluid pressure is exhausted from the table raising cylinder I0.Consequently the weight of table 20 and the assembly thereon carries thetable to its down position.

Near the end of the tables downward movement table pad I 54a again tripstable-down limit switch I56, and as a result of this switch beingtripped fluid pressure is admitted to cylinders I20 which turn theroll-over clamping heads C 180. See Fig. 12. The rotatable jaws I24 arehinged on these clamping heads and hence the assembly of flasks arelikewise rotated 180. The drag flask H4 is now uppermost. The squeezedsand in flasks is not disturbed and cannot fall out during thisroll-over operation because the rotatable jaws grip the squeeze-boardswhich I bear against the sand only. This arrangement has the advantagethat special clamps are not necessary to hold the two flasks together.

Near the end of 180 rotation of the roll-over clamping head C aroll-over limit switch I10 mounted on the front of one of the legs istripped by a stop I'I2a mounted on a vertically disposed rod I12 theupper end of which is pivotally secured to segment gear hub I32a, and asa result of this switch being tripped fluid pressure is admitted to thetable raising cylinder II) to bring table 20 back up to its up positionto support the weight of the now-turnedover assembly of flasks and matchplate. As the table 20 moves upwardtable-up limit switch I is againtripped, and the tripping of this latter switch causes fluid pressure tobe introduced into chambers 68b in the roll-over clamping heads C toopen the rotatable jaws I24. The assembly of flasks and match plate isthen resting on table 20. In .addition, the closing of table-up limitswitch I60 causes fluid pressure to be admitted to cylinders 56 to swingclamping legs 50 outward from table 20 to their out position. See Fig.13.

As the clamping legs 50 reach the end of their 10 outward swing the bar50d associated with each trips 2. clamping-leg-out limit switch I14, andas a result of these switches being tripped fluid pressure is exhaustedfrom the table raising cylinder I0. Thereupon on the weight of table 20and the assembly thereon returns the table to its down position. Thiscompletes the machine cycle.

After this series of operations by the machine both flasks arecompleted, the sand in the drag flask I I4 having been hand-tamped, asdescribed, and the sand in the cope flask [it having been squeezed bythe machine. Furthermore the assembly of flasks and match plate had beenturned over by the machine, so that as it rests on the table 20-now inits down position-the drag flasks I I4 is uppermost.

The purpose of vibrator I06 is to loosen any sand in the flasks whichmay tend to stick to the surface of the match plate. The operator turnson this vibrator and lifts thedrag flask II4 ofl the match plate. Hethen turns this drag flask over, holding its squeeze-board I42 in place,and rests theunit on a bench with its squeeze-board underneath. See Fig.14. This squeeze-board serves as a platform on which the mold rests whenit is put on a conveyor and when the mold is poured.

The match plate H2 is still resting on the cope flask IIS on the table20. The operator places a new empty drag flask H4 in position thereon.Sand is then poured into this new drag flask and a new squeeze-board I42placed on top. See Fig. 15. Again the operator pushes the squeeze-rollbutton I46 and the machine performs the operations just described. Thistime, however, near the end of the 180 roll-over of the roll-overclamping heads C a difierent roll-over limit switch is tripped. In theprevious cycle, the segment gear I32, upon turning effects pivotingmovement of hub I32a in a downward direction, the stop I'I2a carried onrod Il2 thereby tripping switch I10. In the cycle now being described,segment gear I32 turns in an opposite direction effecting pivotingmovement of hub.

I320; in an upward direction thereby causing a second stop I'I2b carriedon rod I72 to trip another roll-over limit switch I16 to efiect theraising of table 20.

When this second machine cycle is completed the finished cope flask [I6is uppermost on the table, and this cope is then drawn by the operatorand set upon the drag finished earlier thus completing a mold. Thereupona new cope flask is placed on the match plate, filled with sand and soon.

There are undoubtedly a number of possible electrical control systemswhich could be associated with my improved machine to provide thesequence of operations I have described above. I have found, however,that the system shown diagrammatically in Fig. 16 is particularly wellsuited for my purposes because it is relatively simple and employsthroughout standard items of electrical equipment.

In some instances, switches bearing the same designating number areshown at several diflerent locations in this Fig. 16. This has been doneto facilitate understanding of the diagram. It will be understood thatin an actual device only one switch is required for all of thosesimilarly designated. Operation of this system will be clear to thoseskilled in the art with the following description.

Main leads I78 and I80 brings power to the circuit from asource (notshown). Switch I82 11 provides means for Shutting off this power whenthe machine is not in use.

Assume switch I82 is closed and the assembly of flasks and match plateon the table" 2! is as shown in Fig. 8. The operator is then ready tostart the machine cycle. Pressing the squeezeroll button switch I48completes a circuit between leads I18 and I80 comprising the buttonswitch I45 and the windings IBda of a normallyopen relay-operated switchI84. The latter switch promptly closes and maintains itself closedthrough a circuit comprising the switch IN, a normally-closedre1ay-0perated switch I36 and the windings IBM of the switch I84. (Whenreference is made herein to normally-open relay-operated switches whatis meant is that these switches are open when no current is fiowinthrough their relay windings; and, likewise, when reference is made tonormally-closed relay-operated switches what is meant is that theseswitches are closed when no current is flowing through their windings.)Because relayoperate'd switch I84 is self-sustaining the operator mayremove his finger from button switch I48 immediately after pressing it.

In addition to the circuit including relay windings IBM another circuitis completed by the closing of switch ass which circuit comprises switch584, switch I86, switch I84 again, 2, normally-closed relay-operatedswitch I88 and the windings I980 of a relay-operated two-way valve Iiiillocated in the fluid pressure line leading to the cylinder 38. Thisvalve is so arranged that current in its relay windings I9Ila positionsthe valve so that fluid pressure is admitted to cylinder 38 to swing thesqueeze-head 36 forward, and, conversely, deenergizing windings I90apositions the valve Hill so as to cause the squeeze-head to be swungback.

Since the last-described completed circuit ineludes the relay windingsnew of valve let current flows through them, and squeezehead 3E swingsto its forward position, closing head forward limit switch I50. Thiscompletes another circuit comprising switch 584, switch I85, switch I88,9. normally-closed relay-operated switch head forward limit switch I58,and the relay windings IQ IUL of a relay-operated oneway valve I9located in the fluid pressure line leading to the squeeze cylinder II].This valve its is so arranged that current in its relay windings 9913acauses the valve to open, and, reversely, when the current stops thevalve closes. Since current flows in windings I94a when head forwardlimit switch I56 is closed fluid pressure is admitted to squeezecylinder IE] to raise the table 2i; and squeeze the sand in the flasksthereon.

When the fluid pressure in cylinder Ii) reaches a predetermined value,calculated to give the sand the proper amount of squeeze, the pressureswitch I52 closes completing a circuit comprising switch ISQ, switchI86, pressure switch I52 and the relay windings I92a of thenormallyclosed relay-operated switch I92. The completion of this circuitopens the normally-closed switch I92 and stops the flow of currentthrough the relay windings I94a of the relay-operated valve i554.Thereupon, fluid pressure being supplied to the squeeze cylinder II) isstopped by the closing of valve' l94; fluid pressure is exhausted fromsqueeze cylinder Ill, and table 20 starts to come down again. I

In addition to opening normally-closed switch I92, the passage ofcurrent through relay windi 92a closes a normally-open switch Illtb alsoassociated with these windings; Closing this lat- 1a ter switchcompletes a circuit comprising switch E86, switch I86, switch IliZb andrelay windings ISM, so that when exhaustion of fluid pressure.

from squeeze cylinder Iii permits pressure switch I52 to reopen currentwill still flow through relay windings I'92a.

As the downward moving table 20 nears its lowermost position the padI54a secured to the depending rod Its engages and closes table downlirriit switch I56. This completes a circuit comprising switch I84,switch I86, switch I922), table" down limit switch Itlii and the relaywindings 588a of normally closed switch I88. Current through these relaywindings Itta causes switch Its to open, whereupon current ceases toflow in the relay windings Iiiiio of valve 5%. As a result this lattervalve operates to cause the squeezehcad 36 to swing back from itsposition abovethe table.

As the squeeze-head 3E nears the end of its backward swing, projectionsec on 1-8 en gages and closes head-back limit switch I58. Thiscompletes a circuit comprising switch I84,- switch I; a selector switchI98 positioned for automatic operation, a normally'mpen relayoperated stitch 58819 which was closed when current flowed through the relaywindings ISM, head back limit switch I58, a normally closedrelay-operated switch 290 and the relay wind ifi ia of valve I54.Current passing through these windings Ifi ia upon completion or thislast mentioned circuit so positions valve I that fluidpr'essure isadmitted to squeeze cylinder I0 to" bring the table 29 up again.-

Upward movement of table 26 reopens tabledown limit switch 56, but therelay windings Itiic remain energized because the normally open switchi881) is closed. Closing of this switch I set permits current to by-passtable-down limit switch his. Thus more particularly, the circuitmaintaining relay windings Idea energized comprises switch E84, switchI135, switch I921, switch Ififib relay windings I88a.

As the upward moving table 2t nears the upper end of its travel, padItta on depending rod I62 engages and closes table-up limit switch Hi0.-Closing this latter switch completes a circuit comprising switch I84,switch I86, switch @381), table-up limit switch Itii, switch E85 againand the relay windings Mia of a relay-operated two-- way valve 262associa ed with the cylinders 56 which move the clamping legs This valve202 is so arranged that current in its relay wind= ings 2cm positionsthe valve so that fluid pressure is admitted to cylinders 56 to swingthe clamping legs 5t toward the table 29, and, reversely, deenergizingwindings 202a positions the valve 202 so as to cause the clamping legsto swing away from the table. Upon completion of the circuitlast-"described the clamping legs begin to swing inward;

As the clamping legs 58 reach the limit of their inward swings, bars 5Msecured to these legs engage and close clamping-leg in limit switchesI64, and when both of these latter switches are thus closed a circuit iscompleted comprising switch 535, switch I86, switch 118%, switch I50,switch 586 again, clamping-leg-in limit switches I64, switch I88 yetagain and the relay windings til -5a of a relay-operated two way valve2% associated with the roll-over clamping heads C. This valve 2M is soarranged that current in its relay windings Etta positions the valve sothat fluid pressure is admitted to cylinder 8 to close the clamping jawsI24, and, reversely, deenergiz tion.

I 13 mg windings 204a positions the valve 204 so as to cause theseclamping jaws to open. Upon completion of the circuit last described thejaws close.

When the fluid pressure which closes the clamping jaws I24 reaches apredetermined value, calculated to insure that the assembly on the table20 is properly gripped, pressure switches I66 and I68 close and completea circuit com prising switch I84, switch I86, switch I88b, switch I60,pressure switch I66, pressure switch I68, a selector switch 206positioned on automatic andthe relay windings 200a of normally-closedrelay-operated switch 200. Energizing the relay windings 200a in thisfashion opens normallyclosed switch 200 and thus stops the flow ofcurrent in relay winding I94a of valve I94. As a consequence, valve I94is positioned so as to exhaust fluid pressure from squeeze cylinder I6,

and table 20 comes down to its lowermost posi- Simultaneously theenergizing of relay windings 200a closes a switch 200i) so that windings200a are held energized by a separate circuit comprising switch I84,switch I86, switch 2001), switch 2001: again and relay windings 200a.

As the table 20 nears the end of its downward movement it again engagesand closes tabledown limit switch I56 and completes a circuit comprisingswitch I84, switch I86, switch 2801), table down limit switch I56,roll-over limit switch I16 which is held closed by stop I12b mounted onrod I12, a normally-closed relay-operated switch 208 and the relaywindings 2I0a of a normallyopen relay-operated switch 2 I0. Currentthrough these relay windings 2I0a closes switch M and completes acircuit comprising switch H6 and the relay windings 2 I200 of arelay-operated twoway valve 2I2 associatedwith the rolleover cylinderI28. This valve 2I2 is so arranged that current in its relay windings2I2a positions it so that fluid pressure is admitted to cylinders I28 torotate the clamping heads C in one direction, and, reversely,deenergizing relay windings 2 I2a positions valve 2 I2 so asto cause theclamping heads to rotate back again in the opposite direction.

The closing of table-down limit switch ,I 56 not only completes acircuit which ultimately causes relay windings 2 I2a to be energized; italso completes another circuit comprising switch I84, switch I86, switch200b, switch I56, a second roll-over limit switch "M which is containedin the same housing *as switch I10 and which is closed when not engagedby stop I12a on rod I12, the normally-closed relay-operated switch 208and the relay windings 2I4a of relay-operated switch 2I4. This completedcircuit closes switch 2I4.

Since the closing of table down limit switch I56 energizes relaywindings 2I2a of valve 2I2 the clamping heads C are rolled-over, and asthey near the end of their 180 rotation stop I120, on rod I12 engagesand closes roll-over limit switch I10 housed in the same casing withroll-over limit switch I10a. The closing of this switch I10 completes acircuit comprising switch I84, switch I86, switch I 10, switch 2I4, bothclamping-legout limit switches I14 which are closed when not tripped, aselector switch .2I6 positioned on automatic and the relay windings I94aof relay-operated valve I94. This completed circuit causes the table tocome up again; I

The energizing of the relay windings 2I4a, as already described, notonly closes the normallyopen switch 2I4, it also opens a normally closedtable-down limit switch I56a.

2I4 maintains relay windings 2| 4a energized through a circuitcomprising switch I84, switch I86, switch 200b, switch 2001) again,switch 2I4 and relay windings 2 I4a.

As the upward moving table 20 nears the upper limit of its travel, padI62d carried on rod I62 once again engages and closes table-up limitswitch I60, and the closing of this latter switch completes a circuitcomprising switch I84, switch I86, switch I881), table-up limit switch I60, switch I60 again, switch 2I4 and the relay windings I86a ofrelay-operated switch I86. Energizing of relay windings I86a in thisfashion opens switch I86 and stops the flow of current through relaywindings 204a of valve 204. Since pressure-operated switches I66 and I68are in parallel with open switch I86 insofar as relay windings 202a ofvalve 202 are concerned, current can still flow to relay windings 202afrom either of the now closed pressure-switches. However, clamping jawsI24 open as a consequence of deenergizing relay windings 20400 of valve204, and when the fluid pressure which held these jaws closed issufliciently reduced pressure operated switches I66 and I68 open andstop the flow of current through relay windings 202a of valve 202. Thiscauses clamping legs 50 to swing away from the table 20.

Energizing relay windings I86a not only opens relay switch I86, it alsocloses a normally-open switch I86b operated by the same relay I86a. As aresult of switch I861) closing relay winding I86a are maintainedenergized by a completed circuit comprising switch I84, a table-downlimit switch I66a which is contained in the same housing with table-downlimit switch I56 and which is closed when not tripped, switch I86?) andthe relay windings I86a. With this arrangement once relay windings I86aare energized they are maintained energized to the end of the machinecycle" regardless of the position of table-up-limit switch I60.

As the clamping legs near the end of their outward swing the bar 5012 oneach engages and opens its associated clamping-leg-out limit switch I14and the flow of current through relay windings I84a of valve I94 isstopped. As a result,

the table 20 starts to move down once more, and when the table nears theend of its downward movement it trips and opens normally-closed Sinceswitch I86 is also open at this point all circuits between leads I18 andI are broken, and the machine cycle is completed. The sand in the flaskshas been squeezed and the assembly of flasks and match plate has beenturned over on the table. The operator then removes the uppermost flaskfrom I the assembly, sets it aside and replaces it with an empty flask.This latter flask he then fills with sand andprovides a squeeze-boardtherefor.

When the operator next presses the squeezeroll button the electricalcontrol circuits behave in the same manner as above described until thepoint is reached where the clamping heads C are ready to roll over. Justprior to this point the table 20 was moving downward, and when itreaches the lower limit of its travel pad I541; carried on rod I54engages and closes table-down limit switch I56. This time the closing ofthis latter switch completes a circuit comprising switch I84, switchI86, switch 2007), switch I56, switch I 10 which was closed at the endof the previous cycle, normally-closed switch 2I4b and the relaywindings 208a of normally-closed relay-operated switch 203. Completionof this circuit also closes a normally-open switch 2&3?) associated withthe relay windings 233a. and these windings 2338a are thereaftermaintained energized by a completed circuit comprising switch I84,switch I85, switch 243%, switch limb again, switch 2981: and relaywindings 298a.

In addition to closing switch 268?), energizing of relay windingsv 2&811opens the normally-closed switch 2%, as has been noted, and the openingof this switch 2% stops the flow of current through relay windings 2!tie of switch 2 Ill. As a consequence switch m opens, windings Zircofvalve 2E2 are deenergized and fluid pressure is admitted to roll-overcylinders I28 to rotate the clamping heads C back again 180.

As the clamping heads reach the end of this last-mentioned rotation thestop IIZb carried on red I12 again engages and closes roll-over limitswitch H6, and the closing of this latter switch completes a circuitcomprising switch 58d, switch I85, roll-over limit switch iiii, switch208b, clamp ing-leg-out limit switches I'M which are closed when nottripped, selector switch 2l6 positioned ,on automatic and the relaywindings Hitsof valve w l. Jurrent through these relay windings waspositions valve it l so that table 28 starts'to come up, and when itreaches the upper limit of its travel pad H5212 carried on rod I62engages and closes table-up-limit switch I50. Closing this switch itiicompletes a circuit comprising switch I34, switch iiili, switch I881),switch E60, switch Hii] again, switch 20% and relay windings ISEa ofswitch I86.

Current through these relay windings iiilia causes switch I86 to openand thus deenergizes relay windings 2M0. of valve 2%, whereupon clampingjaws IZQ open as before, and when the fluid pressure which held thesejaws closed is sufficiently reduced pressure valves Hi6 and I68 open andstop the flow of current through relay windings 26251 of valve 282, asabove described. Consequently valve 2i'i2 is positioned so that theclamping legs t swing away from the tableZIl.

When these clamping legs near the end of their outward swing the bar 5ndon each engages and opens its associated clamping-leg-out limit switchH4, and the opening of these latter switches deenergizes relay windingsHit-w of valve I94. As a result the table starts down again, and when itreaches the lower end of its travel it engages and opens table-downlimit switch Nita. Since switch I86 is open at this point, openingswitch [56d breaks all the circuits between leads I18 and IE9 and againthe machine cycle is completed. The sand in the flasks has again beensqueezed and the assembly of flasks and. match plate again turned overon the table.

The operator removes the uppermost flask from the assembly, sets it onthe previously set aside flask to form a completed mold, and replaces itwith an empty flask. This latter flask he then fllls with sand, and soon.

It will be seen from Fig. 16 that there are a number of switches and arelay which have not thus far been described. These switches and relaysare provided so that if the operator wishes he can accomplish the fullmachine cycle one step at a time, pushing a button for each step.

Thus assume that such intermittent operation is desired. First of allthe operator positions each of the selector switches 98, 206 and ZIG onmanual. Next he pushes button switch M5. The squeeze-head 38 will comeforward, the table 20 will come'up and squeeze the sand in the fiasks,

the table: will go down again and the squeezehead will swing back.Nothing further will happen because selector switch 198 is positioned onmanua Next the operator must push a button switch 2 l8. This energizesthe relay windings 225m of a normally-open relay-operated switch 22c andthe consequent closing of this switch 22o maintains relay windings 226aenergized. In addition, closing of switch 220 completes a circuitby-passing selector switch I98 and the following operations result: Thetable 29 comes up; the clamping legs 50 swing'in toward the table; andthe jaws close to grip the assembly of flasks and match plate. Nothingfurther will happen because selector switch 206' is positioned on mannaNext the operator must push a button switch 222. Thi energizes the relaywindings 283a of switches 2'00 and 20612 and the following operationsresult: The table 26 moves to its down position, and the assembly offlasks and match plate is turned over. Nothing further will happenbecause selector switch Zit is positioned on manual.

Next the operator must push a button switch 224. This completes acircuit energizing the windings ISM/t of relay Valve I84; and thefollowing operations result: The table 20 moves to its up position; thejaws I24 open; the clamping legs 5%) swing away from the table; and thetable moves to its down position.

Just as there are a number of electrical control systems which may beemployed with my improved machine, there are undoubtedly a number offluid pressure control systems that could be used. I have found,however, that the fluid pressure control ystem shown diagrammatically inFig; 17 is particularly well suited for association with the electricalcontrol system of Fig. 16. The various parts of the machinefragmentarily shown in Fig. 17 are in the positions they assume when thecycle has progressed to the stage shown in This position i achieved invalve it?! by spring means 228, in valve I94 by spring means 2-30, invalve 2532 by spring means, 232, in valve 284 by spring means 234 and invalve '2 l 2 by spring means 236. Speed controllers 238 are locatedthrough out to prevent too rapid movement of the movable parts.

I claim:

1. A machine for making molds which comprises a movable table forsupporting flasks, a squeeze-head movable into cooperative relation withsaid table, means for moving said squeezehead, means for moving saidtable toward said squeeze-head. to apply pressure to the contents ofsaid flasks, rotatable clamping jaws locatedon opposite sides of saidtable and movable theretoward, means for moving said jaws toward saidtable, means for closing said jaws to grip said flasks and means forrotating said jaws with said flasks gripped therebetween.

2. A machine for making two-part molds by the match plate method whichmachine comprises a vertically movable table for supporting jaws toinvert the flasks on said table.

3. A machine for making two-part sand molds by the match plate methodwhich machine comprises a vertically movable table for supporting twoflasks which are assembled thereon one above the other with a matchplate between them, a squeeze-head movable into a position above saidtable, means for moving said squeeze-head into said position above saidtable, means for raising said table toward said squeeze-head until anupper squeeze-board located on top of the uppermost flask engages saidsqueeze-head and by said engagement tightly packs the contents of bothsaid flasks, means for lowering said table, means for moving saidsqueeze-head from said position above said table, rotatable clampingjaws located on opposite sides of said table and movable theretoward,means for holding said jaws open, means for moving said open jaws towardsaid table so that when said table has been raised a predetermineddistance by said table-raising means said open jaws embrace the oppositeends of the assembly of flasks and match plate, means for closing saidjaws until each bars against said upper squeeze-board and against alower squeezeboard on which the lowermost flask rests, means forrotating said jaws to invert said flasks when said table has beenlowered by said table-lowering means, and means to open said jaws andadditional means to move said jaws away from said table when said tablehas been raised by said table-raising means to support said invertedflasks.

4. A machine for producing two-part sand molds with a match plate whichmachine comprises a vertically movable table for supporting a cope flaskand a drag flask assembled thereon one above the other with said matchplate between them, a squeeze-head movable into a position above saidtable, means for moving said squeeze-head into said position above saidtable, means for raising said table toward said squeezehead until anupper squeeze-board resting on the contents of the uppermost flaskengages said squeeze-head, said engagement tightly packing the contentsof said uppermost flask between said upper squeeze-board and said matchplate and in addition tightly packing the contents of said lowermostflask between said match plate and a lower squeeze-board on which saidlowermost flask rests, means for lowering said table, means for movingsaid squeeze-head from said position above said table, movable framemembers located on opposite sides of said table, clamping jaws rotatablymounted on said movable frame members, means for holding said clampingjaws open, means for moving said movable frame members toward said tableso that when said table has been raiseda predetermined distance by saidtable-raising means said open clamping jaws extend around the oppositeends of said assembled flasks, means for closing said clamping jawsuntil one jaw piece of each engages the upper surface of said uppersqueeze-board and the other jaw piece of each engages the lower surfaceof said lower squeeze-board, means for rotating said clamping jaws toinvert said flasks when said table has been lowered by saidtable-1owering means, and means for opening said clamping jaws andadditional means for moving said movable frame members away from saidtable when said table has been raised by said table-raising means tosupport said inverted flasks.

5. A machine for producing two-part sand molds by the match plate methodwhich machine comprises a vertically movable table for supportingcertain elements which form no part of this machine, more particularly acope flask and a drag flask which may be manually assembled on saidtable one above the other with said match plate between them preparatoryto the operation of said machine, said lowermost flask having beenfilled with sand and resting on a lower squeeze-board which in turnrests on said table and said uppermost flask also having been filledwith sand and having an upper squeeze-board resting thereon, asqueeze-head movable into a position above said table, means for movingsaid squeeze-head into said position above said table, means for raisingsaid table toward said squeeze-head until said upper squeeze-boardengages said squeeze-head to pack the sand in the flasks between theirrespective squeeze-boards and said match plate, means for lowering saidtable, means for moving said squeeze-head from said position above saidtable, frame members located on opposite sides of said table. and havingtheir lower ends pivoted near the base thereof so that the upper ends ofsaid frame members can swing toward and away from said table, clampingjaws rotatably mounted in said upper ends of said frame members so thatsaid clamping jaws have a common axis of rotation when said framemembers are swung toward said table, means for holding the jaw pieces ofsaid clamping jaws open, means for swinging said upper ends of saidpivoted frame members toward said table so that when said table has beenraised a pretetermined distance by said table-raising means one jawpiece in each said clamping jaw is positioned above an end of said uppersqueezeboard and the other jaw piece in each said clamping jaw ispositioned below an end of said lower squeeze-board, means for closingsaid clamping jaws until said jaw pieces of each bear firmly againstsaid squeeze-board ends, means for rotating said clamping jaws 180 toinvert said flasks held thereby when said table has been lowered by saidtable-lowering means, and means for opening said clamping jaws andadditional means for swinging said upper ends of said frame members awayfrom said table when said table has been raised by said table-raisingmeans to support said inverted flasks.

References Cited in the flle of this patent UNITED STATES PATENTS

